This project aims to further develop a breakthrough detector technology for Transmission Electron Microscopy (TEM). The detector, the Direct Detection Device (DDD) is vastly superior to Charge Coupled Device (CCD) detectors currently in use. In particular, the DDD delivers improved resolution, signal-to-noise ratio (SNR) and speed. As an enabling technology, many fields in which the TEM is a critical tool stand to benefit, but the DDD advantages will be of particular value in the field of biological cryo-EM where current detector performance severely limits the information that can be gleaned from specimens because of their extreme sensitivity to dose. Improved detector performance will translate directly to better 3-dimensional structures of macromolecules, viruses, and organelles. New problems that were previously intractable, will become solvable, and the goal of achieving near atomic resolution 3-D TEM structures will be attainable in many more cases. Ultimately, the utility of cryo-EM as a tool for elucidating structure-function relationships will take a leap forward, accelerating progress in understanding disease and designing cures. This project will advance the highly promising results from the earlier phase to ultimately deliver a commercially practical camera system that offers all of the benefits of the DDD and digital image capture plus the resolution and field of view of photographic film. The project has a sensor development component including extending lifetime to well beyond 1 year, further improving sensitivity as measured by the Detective Quantum Efficiency (DQE) figure of merit, and increasing the format (number of pixels) to equal that of photographic film. The project also has equally important system engineering and software components. Deliverables include a compact and modular design that is integrated with instruments commonly used in the field, as well as integration with the most important and widely used automation and data collection software packages. PUBLIC HEALTH RELEVANCE: Upon successful completion, this project will deliver an enabling technology for users of transmission electron microscopy (TEM) that will provide significantly higher quality imaging of biologically significant materials. The project will provide important benefits to academic, government, institutional, and private sector biotechnology researchers as they strive to use 3-Dimensional structures of organelles, viruses and macro- molecules to elucidate structure-function relationships and mechanisms of action to understand and cure disease.